Medical technology station and method of use

ABSTRACT

A medical station includes a movable cart and a cassette system. The cassette system includes a housing, a plurality of lockable drawers slidably mounted to the housing, and a drawer manual override configured to allow a hardware key to mechanically unlatch all of the drawers so that the drawers are capable of opening.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Non-Provisional ApplicationSerial No. 16/910,988, filed on Jun. 24, 2020, which is a continuationof U.S. Non-Provisional Application Serial No. 15/975,860, filed on May10, 2018, which is a continuation of PCT/US16/61911 filed on Nov. 14,2016, which application claims the priority benefit of U.S. ProvisionalApplication Serial No. 62/255,336 filed on Nov. 13, 2015, all of whichare incorporated by reference herein in their entirety.

BACKGROUND

Prescriptions are dispensed in hospitals, nursing homes and otherinstitutions generally by hand. Nurses and medical staff will collectthe needed medication at an internal pharmacy, such as at an automateddispensing cabinet (an “ADC,” a vending machine-style cabinet located ina ward that dispenses medication to nurses once it is prescribed for apatient). The nurse will collect the medications for each patient fordistribution. The nurse will then dispense the medication to patientswhen doing his/her rounds. These methods of delivering medication haveinherent distribution errors, and these errors can result in patientsconsuming the improper medication or incorrect dosage, with possibleadverse drug reactions, including death. A better distribution system isneeded to reduce distribution errors.

SUMMARY

The invention disclosed herein is directed to a medical technologystation for prescription dispensing and a method of using the station.The station uses a mobile wheeled cart that includes a number ofassorted and reconfigurable drawers, where each drawer will generally beassigned to a single patient for a given medication distributionworkflow. The drawers on the cart are electronically recognizable, byemploying a unique identifier, such as inclusion of an RFID tag in eachdrawer, or another electronic identification device. The station’sdrawers are generally kept in a locked inaccessible state, unlesselectronically opened in response to certain preset activation signals.The station includes a display device, such as a monitor or tabletinterface. The station also includes an input device, such as akeyboard, mouse, or touch screen. Optionally, the system can include areader or scanner for barcodes or hash tags. The system also includes aprocessor and computer memory to interface the station equipment. Theprocessor and equipment may be located at the station, such as a tabletor laptop. The computer memory may be located on the cart, remote fromthe cart, or both. The processor is in communication with the memory.The dispensing station uses a novel cassette system to accommodate thedrawers within the mobile station.

In use, each patient along a distribution workflow will be assigned oneof more particular drawers on the cart, such as by entry of the patientidentifier and/or an associated drawer identifier into the system’smemory. In use, the medical staff will preferably take an unloaded cartto a dispensing station (such as the ADC internal pharmacy). The staffloads the drawers with medication to be delivered. For instance, at thepharmacy, the medical staff will log into the cart station. The staffwill enter a patient ID to access that patient’s drawer, open thatpatient’s drawer, and load the predetermined patient medication. Thisprocess is repeated until all patients' drawers are each loaded withtheir medications. Alternatively, all drawers can be opened at once, orall drawers in a particular cassette will be opened, and the staff willload each drawer with the medication for the patient assigned to eachdrawer. To dispense the medications, the staff will then roll the loadedstation to particular patient’s location, access the drawer using one ofthe input devices (to identify the patient or drawer), and dispense thatpatient’s medication. The system includes safety features, for instance,the drawers lack pulls or handles and can only be opened electronicallyby a credentialed (authorized) user and, in some embodiments), one ormore patient identifiers are required to open specific drawers, anauthorized user’s inability to access different patient’s drawers at thesame time; and the automatic retraction and closure of a drawer that hasnot been fully opened within a predetermined period of time.

The above summary is not intended to describe each illustratedembodiment or every possible implementation. These and other features,aspects, and advantages of the present invention will become betterunderstood with regard to the following description, appended claims,and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying Figures, where like reference numerals refer toidentical or functionally similar elements throughout the separateviews, serve to illustrate further various embodiments and to explainvarious principles and advantages in accordance with the presentinvention:

FIG. 1 is a perspective view of one embodiment of the dispensingstation.

FIG. 1A is a perspective view of another embodiment of the dispensingstation.

FIG. 2A is a detailed perspective view of one embodiment of thedispensing station depicting a drawer in the almost closed position.

FIG. 2B is a detailed perspective view of one embodiment of thedispensing station depicting a drawer in a fully opened position.

FIG. 2C is a rear perspective view of one embodiment of a cassette.

FIG. 3A is a front perspective view of one embodiment of a cassette witha handle open or deployed and pivoted upwardly.

FIG. 3B is a front perspective view of one embodiment of a cassette witha handle closed.

FIG. 3C is a front perspective view of the embodiment of the cassette inFIG. 3B with the drawers removed.

FIG. 4A is a detailed perspective side view of one embodiment of acassette mounted in a housing with the cassette handle closed.

FIG. 4B is a detailed perspective side view of FIG. 4A with the cassettehandle ejected or deployed.

FIG. 4C is a detailed perspective side view of FIG. 4B with the cassettepartially removed from the housing.

FIG. 4D is a detailed perspective side view of FIG. 4A with the cassetteremoved from the station.

FIG. 5 is a rear perspective view of a cassette with the rear panelremoved.

FIG. 6A is a perspective front view of a small drawer.

FIG. 6B is a perspective rear view of a small drawer.

FIG. 7 is a perspective rear view of a medium drawer.

FIG. 8 is a perspective rear view of a large drawer.

FIG. 9 is a front elevation view of one embodiment of the cassette rearpartition.

FIG. 10 is a rear elevation view of one embodiment of the cassette rearpartition.

FIG. 11 is another embodiment of the station.

FIG. 12 is a screenshot depicting system configuration.

FIG. 13 is a screenshot depicting drawer assignment.

FIG. 14 is a screenshot depicting monitoring drawer open status.

FIG. 15A is a front perspective view of one embodiment of the hollowhousing.

FIG. 15B is a detailed view of the housing of FIG. 15A depicting thecassette handle actuator.

FIG. 15C is a side elevation of the one embodiment of a cassette handleactuator.

FIG. 16A is a perspective view of one embodiment of an actuatablecassette handle.

FIG. 16B is a perspective view of the handle of FIG. 16A with the topcover removed.

FIG. 17 is a rear perspective view of one embodiment of the centerpartition of a housing.

FIG. 18 is a prospective view a cart with a battery bridging stationattached.

V. DETAILED DESCRIPTION

Detailed embodiments of the present invention are disclosed herein;however, it is to be understood that the disclosed embodiments aremerely exemplary of the invention, which can be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present invention in virtually anyappropriately detailed structure. Alternate embodiments may be devisedwithout departing from the spirit or the scope of the invention.Further, the terms and phrases used herein are not intended to belimiting; but rather, to provide an understandable description of theinvention. While the specification concludes with claims defining thefeatures of the invention that are regarded as novel, it is believedthat the invention will be better understood from a consideration of thefollowing description in conjunction with the drawing Figures, in whichlike reference numerals are carried forward.

As used herein, the terms “a” or “an” are defined as one or more thanone. The term “plurality,” as used herein, is defined as two or morethan two. The term “another,” as used herein, is defined as at least asecond or more. The terms “comprises,” “comprising,” or any othervariation thereof are intended to cover a non-exclusive inclusion, suchthat a process, method, article, or apparatus that comprises a list ofelements does not include only those elements, but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. An element proceeded by “comprises ... a” doesnot, without more constraints, preclude the existence of additionalidentical elements in the process, method, article, or apparatus thatcomprises the element. The terms “including,” “having,” or “featuring,”as used herein, are defined as comprising (i.e., open language). Theterm “coupled,” as used herein, is defined as connected, although notnecessarily directly, and not necessarily mechanically. As used herein,the term “about” or “approximately” applies to all numeric values,whether or not explicitly indicated. These terms generally refer to arange of numbers that one of skill in the art would consider equivalentto the recited values (i.e., having the same function or result). Inmany instances, these terms may include numbers that are rounded to thenearest significant Figure. Relational terms such as first and second,top and bottom, right and left, and the like may be used solely todistinguish one entity or action from another entity or action withoutnecessarily requiring or implying any actual such relationship or orderbetween such entities or actions. Defined terms include:

-   ADC - Automated Dispensing Cabinet. A vending machine-style cabinet    located in a ward that dispenses medication to nurses once it is    prescribed for a patient. A common brand of ADC is Pyxis - ADCs are    often referred to as Pyxis machines.-   BCMA - Bar Code Medication Administration. A term used to describe a    system where medication is bar coded and scanned prior to being    administered to a patient to ensure it is the right drug/dosage.-   Closed loop system - used to describe any workflow where there is    end to end traceability and accountability throughout the medication    distribution process.-   HIS - Healthcare Information System. An umbrella term used to refer    to software that stores hospital and patient information, usually    accessed via the hospital’s communications network.-   HL7 integration - one software communications protocol for sharing    patient information between different software applications. The    disclosed station can use HL7 to retrieve patient information from a    hospital’s HIS.-   Unit dose - A single pill, syringe or vial of medication,    individually packaged in its lowest common dosage. This is    increasingly the type of medication used in hospitals and stored in    medication drawers.-   Workflow - the series of steps necessary to complete a specific    process, such as getting medication from an ADC to a patient.-   Drawer - A removable storage cubicle that is contained in a    cassette. A drawer will occupy one or more compartments. In one    embodiment, each drawer may be assigned to a single patient, or    designated as a storage drawer. Each drawer can be opened    individually through commands entered in the system by an authorized    user. In a preferred embodiment, each drawer contains at least one    electronically readable identifier, such as contained in an RFID tag    or bar code, which is used to electronically identify the drawers.    In one embodiment, there are 3 sizes of drawers.-   Cassette - A cassette is a storage frame into which drawers are    loaded. Cassettes are removable from the station, and in one    embodiment, the cassette is removable from the cart through commands    to eject the cassette handle. Cassettes are in electronic    communication with the station’s processor. The interior of each    cassette is subdivided into compartments. Drawers inserted into the    cassette occupy one or more compartments. In one embodiment, each    cassette has shelves which can be removed to allow for different    drawer configurations.-   Compartment - a portion of the interior of a cassette that is    adapted to accommodate the smallest drawer size. The cassette    embodiments depicted have eight compartments, but could have more or    less.-   Housing - The housing is the large hollow module fixedly attached to    the cart. In one embodiment, cassettes are loaded or mounted in the    housing from the left and right-hand sides of the station. A lower    housing can be attached to an upper housing for a high-capacity    station, such as shown in FIG. 1A.-   Location bar code -a bar code or hash code that can be placed in the    hospital in specific areas. Some areas may be designated as “safe    areas” to fill and restock medication drawers. For instance, a    location bar code may be placed next to an ADC. Within the station’s    software, users can be prompted to scan location bar codes to unlock    the drawers to initiate the filling or restocking process.

Described now are exemplary embodiments of the present invention. Oneembodiment of the station 1 is shown in FIG. 1 . The station 1preferably includes a movable cart, such as a rollable cart 10, wheremovement is provided by wheels or casters at the base of the cart. Onepreferred cart is a Humanscale T7 cart, which is based on the adjustablefeatures described in U.S. Pat. No. 9,038,549, hereby incorporated byreference in its entirety. The T7 cart includes a portable power source100, such as a rechargeable battery, generally stored in the bottom ofthe cart. In other embodiments, a power station, including a battery,and a battery bridge station 99 containing an internal battery, such asan Elora battery interface available from Anton Bauer of Vitec GroupPlc, of Richmond UK can be mounted to the back of the station or cart.See FIG. 18 . The battery bridge allows a user to swap out a dischargedbattery without losing power to the cart (via the internal battery ofthe bridge) during the swap. The T7 cart is height adjustable (generallyelectronically adjustable via system software) with a center telescopingsupport stand 9. Preferably located on the cart 10 is a computer systemcomprising one or more input devices 20, a local onboard processor 30and computer memory, and a visual display device 40. The input device20, a local onboard processor 30, the computer memory and visual displaydevice 40 can be a single unit, such as a tablet or laptop, or separateunits. In other embodiments, a movable cart is not used, and the station(including the computer system, housing and cassette, as laterdescribed, is a stand-alone device generally located at a fixed location(such as in a pharmacy).

As shown, the cart 10 includes a work surface 11 and a keyboard mount orshelf 12 extending outwardly from the main body of the cart 10. In theembodiment of FIG. 1 , a monitor 41 is mounted on a pivotable arm 15above the work surface 11. Located on the cart is a computer, includinga processor, local computer memory, input/output and display device.Shown on the keyboard mount 12 are input devices, such as a keyboard 21and mouse 22. In the embodiment shown, a laptop or tablet can be locatedon the work surface or below the work surface. Also shown in FIG. 1 is asecond processing device, display, and input device, represented by atablet 25 with a touch screen interface.

In one embodiment, attached to the underside of the work surface 11 isan upper cassette housing 90, into which removable cassettes 50 can beinserted. As shown in FIG. 4D, the cassette housing 90 is a hollowrectangular shell having two opposing open sides (a right and a leftopen side, the right side is shown in FIG. 4D). As shown in FIG. 15A,positioned in the interior center of the housing 90 are center verticaldividers 93 separating the housing interior into at least two sections,a left housing section associated with a left center divider 93, and aright housing section associated with right center divider 93. In theembodiment shown, a removable cassette 50 (see FIG. 3A) can be insertedinto each housing section. Two housings may be mounted on the cart, anupper housing 90 and a lower housing 95, such as shown in FIG. 1A.

In a preferred embodiment, the chassis of the cart has a telescopingheight adjustable support column 9, and with a telescoping supportcolumn, the upper housing 90 is generally mounted to the underside ofthe work surface 11 to avoid interference with the movement of thetelescoping arm 9. In this embodiment, shown in FIG. 1A, a lower housing95 is preferably mounted to the underside of the upper housing 90. Withtwo housings, the cart 10 is able to accommodate four cassettes 50, nextdescribed. Power and communications to the lower cassette housing 95 isprovided by a wiring harness that may be coupled to the housing wiringharness in the first or upper cassette housing 90. Instead of a daisychained bus system, a linear bus could be used where each housingrepresents a separate node on a bus system, and each receives allhousing communications but only responds to communications addressed tothat particular housing. Each housing 90 (upper or lower), and housingsections (right or left) are addressable on the communications bus, andthe address is imbedded in instructions/commands/queries and isinterpreted in microcontroller firmware mounted on a printed circuitboard (PCB) 300 positioned on a center divider 93 for each respectivehousing 95 and 90. (See FIG. 17 ). This micro-controlled firmware, inconjunction with the system software contained in or accessible on thesystem processor 30 and microcontroller firmware located in the cassette(such as on a cassette PCB), will direct instructions and commands fromthe user, via the system processor, to the proper housing, via a commonpower and communications bus (such as wiring harness or harnesses, andfrom the housing to the proper cassette and cassette component, as laterdescribed.

Communications from the cassette housing 90, 95 to the cassettes isprovided through the center dividers 93 in each housing 90, 95. Eachcenter divider 93 includes an electronic interface device 94 that iscoupled to the power and communications bus, and each interface device94 will couple or interface with a cassette electronic interface device64 on the rear of a cassette 50 (see FIG. 2C). In the embodiment shownin FIG. 5 , the housing electronic interface device 93 is a six-prongmale connector, and the cassette interface device 64 is a correspondinginter-mating female plug (see FIG. 2C). The housing electrical interfacedevice 94 is coupled to a housing wiring harness (not shown) thatinterfaces the housing firmware on the PCB 300. An additional wiringharness couples the firmware to a plug at the top of the housing 90 (seeFIG. 17 ) for connection to the cart’s computer system and cart powersupply.

These wiring harnesses, as a common communications and power bus, willsupply power and control/ communications from the station’s battery andprocessor, to the components and equipment located in the individualcassettes 50. The system is thus able to route communications to theappropriate component by using an address scheme for each component (asinterpreted by the firmware in the cassette, if present). If cassettefirmware is used, the firmware may have an internal database of thecomponents positioned on the cassette board, and these components may beassociated, at the cassette board level, with a drawer identifier ordrawer location. The firmware may also have access to a modifiablememory table on the PCB to store a local map or image of the draweridentities and associated positions in the cassette that can be filledin response to a read ID command). The overall equipment configuration(and equipment addresses) for each cassette is preferably maintained, orpartially maintained, in a system database, which may be stored in localmemory for use by the system processor or in a remote server memory, orin both locations.

One embodiment of the cassette 50 is shown in FIGS. 3A-3C. As shown inFIG. 3C, the cassette 50 is a six-sided hollow rectangular frame 53 withone open side, into which a number of drawers 70 may be slidablypositioned in the interior of the frame 53. The cassette frame 53 shownin FIG. 3C is closed on five sides (rear, top, bottom, side 1 and side2) and open in the front. As shown in FIG. 3C, the cassette frame 53 hasthree horizontal dividers 56 that separate the interior of the cassetteframe 53 into four separate spaces, each space containing twocompartments (two compartments per divided space, for a total of eightcompartments per cassette). These horizontal dividers 56 slide in slitson the frame 53 interior side walls, and can be repositioned on theframe 53 to allow customization of the drawer configuration of thecassette 50 to accommodate 2-8 drawers 70 in each cassette. The topfacing surface of each divider 56 may have one or more shoulders orchannels to interface a comparable channel or shoulder on a drawerbottom, to act as a drawer guide.

Located in the interior rear of the cassette frame 53, is a rearvertical partition 63, on which equipment may be mounted (see FIG. 5 ).For instance, mounted on this partition 63 are a series of actuators 200and actuator latches 201. In a preferred embodiment, each compartment isassociated with one actuator 200 and associated actuator latch 201. Therear panel of the cassette frame 53 is removably attached to the body ofthe frame to allow user access to the drawer actuators 200, actuatorlatches 201, and drawer sensors positioned on the rear verticalpartition 63. As shown in FIG. 9 , the front terminating end 203 of anactuator latch 201 is U-shaped, with the open end of the U-shapeupwardly facing, but other shapes could be used.

Coupled to the top front surface of the frame 53 is a spring-loadedU-shaped handle 51 (see FIGS. 3A and 3B and 5 ). The handle 51 ispivotably mounted to the top of the frame 53. Note that the handle 51 isflush with the frame 53 sides and frame front. The handle 51, in aretracted or closed position, cannot be grasped by an operator, that is,the handle is inaccessible in the closed position (see FIG. 4A).Consequently, the cassette 53 cannot be removed from the housing 90until the handle is electronically unlatched/ejected by a user. Thehandle 51 is pivotally connected to a slidable spring loaded latchingplate 2000 (see FIGS. 16A and 16B), and this plate 2000 is latched inplace with latch members 3000 positioned on the upper interior of thehousing 90. See FIG. 15B. As shown in FIG. 15C, the latch member 3000 isa dual actuatable latch member having a left latch 3001 and a rightlatch 3002, separately actuatable. The left latch member 3001 will latchand lock to the slidable plate 2000 on the left cassette 50, and theright latch member 3002 will latch and lock to the slidable plate 2000in the right cassette 50. When latched and locked, the handle 51 is inthe retracted position (flush with the cassette drawers). To eject ahandle 51 to a released or deployed position, as shown in FIG. 4B, theuser will activate an eject command from the input device. This commandwill activate the servo or solenoid or other actuator associated withthe selected cassette, to activate the appropriate left or right latch3001 or 3002. On actuation, the latch 3001 or 3002, will disengage fromthe sliding handle plate 2000, allowing the plate 2000 and attachedhandle 51 to slide forward by action of springs 2001, which deploys thehandle to a position where the handle extends past the front of thecassette frame 53 and allows a user to grasp the handle 51, as shown inFIG. 4B. One sequence of steps to eject a cassette handle, in oneversion of the station (the Medlink lite version), is shown in Table 1.Another sequence of steps to eject a cassette handle in another versionof the station (the Medlink Pro version) is shown in Table 2. Toreposition the handle 51 in the closed state, the handle 51 is pushedinwardly until it is flush with the cassette front surface, where thehandle latch will reengage the sliding plate 2000. When a cassette 50 isinstalled in a housing 90, the user may also deploy the handle 51manually in the event of a power failure, by inserting a key in thehousing, which turns a linkage to manually move the latch actuators to areleased position. Switches in the housing (in electrical communicatingwith the processor) may be associated with each cassette, and the switchstate can be used as an indicator of the presence or absence of acassette.

Table 1 Cassette Ejection - MedLink Lite User action/ user displaySystem Computer Action 1 In Cassette view, touch the eject button in thecenter of the cassette graphic. Receive request to eject cassette 2 Thecassettes will highlight in blue. Touch the cassette you wish to eject.Update screen Send command to eject selected cassette on the system bus3 The cassette handle will pop out of the housing, allowing you toremove it. Continue to eject additional cassettes if required, or touchthe Cancel button to return to Cassette View. Poll system Cassette failsto respond 4 Remove the cassette from the housing by pulling the handleoutwards. Update screen to show cassette is empty 5 On returning toCassette View, you will see the ejected cassette is shown as empty onthe graphic with no label. Any labelled drawers that were in the removedcassette will also be removed from the drawer list, as they are nolonger available. (Note: on re-insertion, system will recognize drawersthat were stored in local memory, but not new drawers. New drawers willbe displayed as an unassigned drawer, and the local table will beupdated accordingly)

Table 2 Cassette Ejection - MedLink Pro User action/ user display SystemComputer Action 1 Click the icon on top of the cassette to eject thatcassette. Note that all drawers on the chosen cassette must be lockedfirst. If user does not have credentials, the eject icon will bedisabled. Verify credentials of user to allow removal of cassette. If nocredentials, disable eject button. Receive Request to eject cassetteVerify status of all drawers as closed 2 The cassette handle will popout of the housing, allowing you to pull the cassette out and remove it.Send eject handle command on system bus 3 Remove the cassette from thehousing by pulling the handle outwards. Poll system, discover cassetteremoved 4 The screen will update to show the cassette has been removed.Update screen to show cassette removed. (On reinsertion of a cassette,system will discover new cassette then poll for cassette drawerinformation (RFID, size), request drawer identifier/patient identifierfrom server, and repopulate server table with new configuration, andrefresh display with new configuration data)

Once the handle 51 has been deployed, the user can grasp and pull thehandle 51, sliding the cassette 50 toward the user and out of thehousing 90 (see FIGS. 4C and 4D). The handle 51 may then be used totransport the cassette 50, as the handle 51 is pivotably attached to theframe 53 and sliding plate (see FIG. 3A). In the embodiment shown, thehandle 51 may not be repositioned into the retracted position once thecassette 50 is removed from the housing 90, as the locking latches 3001and 3002 are located in the housing 90.

As shown in FIG. 3B, the top exterior facing portion of the cassetteframe 50 has a channel 57 defined therein, which is shaped to slidablyinter-mate with a downwardly facing shoulder 3007 in the interior of thehousing 90, for sliding the frame 53 into the cassette housing 90 toallow the latch actuators 3000 to interact with the slidable plates 2000(see FIG. 15B).

Since the cassette 50 connects into the center divider 93 of the housing90, communications/control and power are provided from the cart 10,through the housing 90 to the vertical partition 63 in the cassette 50.The wiring harness from the cassette plug 64 on the rear of the cassette50 is attached to a PCB (printed circuit board), and from this board,wires connect to the separate components mounted on this rear partition63 in the cassette 50. Communications and control of the components areaccounted for by micro-controlled firmware. This firmware may be mountedon the PCB in the housing center divider 930, in the cassette rearpartition 63, or both. In one embodiment, the addressable command fromthe processor is passed to the firmware in the housing located on ahousing printed circuit board, which, if addressed to a cassette in thehousing, will pass the command to the appropriate cassette (the housingfirmware may strip off the cassette address, leaving the componentaddress (such as actuator address 0-31), and the firmware in thecassette located on the cassette printed circuit board will respond tothe command with the appropriate response,) (such as actuate activator16, or read RFID 00), and communicate status of the command (if needed,such as respond with RFID tag value) back to the housing, which passesthe response to the processor. The system has distributed intelligencewith high level user interface functionality located in the cartprocessor, and the component level interface functionality located infirmware in the housing and the cassette. The cassette microcontrollerfirmware is used to route power and communications signals from thecommon power and communications bus via the six-wire plug (two wires forpower, two wires for addressable communications, and two wires used todifferentiate the upper housing from the lower housing), fordistribution of actions or commands to the equipment on the rearpartition 63 of a cassette (such as actuators, proximity sensors, RFIDreader and antennas). The firmware on the housing 90 will directcommunications to the proper cassette 50 (right or left based on theaddresses provided in the instructions from the system processor. Theprocessor can access the drawer location which is stored on computermemory, where the computer memory is either located on the cart orremotely located, such as on a system server (in a client/serverrelationship where the cart processor is the client in communicationwith and a remote server computer) with drawer information stored on theserver computer memory). In many embodiments, the computer memoryincludes a database which generally has stored drawer identifiers, whichmay include drawer size/drawer location in the cassette interior, wheredrawer location can be specified in a variety of different ways, such asby specifying a compartment(s), or other associated locations, such asactuator locations (e.g., actuator address 0-15), sensor address, orother addresses or locations associated with a compartment or with thedrawer. The database with the configuration map may contain RFID tag orthe unique drawer identifier information (such as on the Medlink Proversion, described later), and associate each RFID information with allother patient identifiers assigned to the particular drawer, whichinformation can be stored in computer memory located remote for thecart, such as in a server computer, the hospital HIS system computermemory), In this client/server embodiment (the client being the cartprocessor and the server being a remotely located computer system withaccess to computer memory), the server system is accessed with either awireless or a wired communication channel. The system will use thisconfiguration map or database for routing instructions and controlsignals, based on input from a user (e.g., open drawer AS). The firmwareon the cassette will decode the instruction from the processor/housingand route the instruction to the final destination, to the appropriateequipment on the cassette partition for action or communication (e.g.,power actuator 8, for instance, or query status of proximity sensor 3).

The following is one embodiment of an address scheme for use in thesystem to address housings, cassettes, and drawer positions:

-   Each housing assembly has a left and a right cassette of drawers    (left and right from viewpoint of T7 operator).-   Within a cassette, the drawer compartments are numbered, by rows,    starting from the upper left position: (0, 1), (2, 3), (4, 5), (6,    7).-   The base address of a left cassette is 0.-   The base address of a right cassette is 8.-   The base address of the upper housing is 0.-   The base address of the lower housing is 16.-   The absolute address of a drawer position is: housing base address +    cassette base address + drawer position number.-   The absolute address of a cassette is: housing base address +    cassette base address.

Each component (latch actuators, electronic reading devices, andproximity sensors, switches) is also addressable (e.g., such as 0-31).The specific type equipment addressed may not be specified in thecommand, as the instruction can inform the cassette firmware of theequipment addressed (e.g., an open command is addressed to actuators; aread ID command is addressed to RFID sensors, etc.).

Drawers 70 are slidably positioned in one or more drawer compartments inthe interior of the frame 53. In a preferred embodiment, drawers 70 areavailable in three sizes, a small drawer that occupies a single cassettecompartment, a medium drawer that occupies two side-by-side cassettecompartments, and a large drawer that occupies four cassette contiguouscompartments (two side-by-side compartments one on top of the other).One embodiment of a single drawer is shown in FIGS. 6A and 6B. As shown,the front of the drawer 70 lacks drawer handles or a grip or graspablefeature, and when closed, the drawer front surface is flush with theouter frame of the cassette. Consequently, when closed, a drawer 70cannot be opened unless unlocked and ejected or opened by the system, aslater described. Each drawer 70 is a rectangular enclosure with an opentop. Preferably, located on the back or rear exterior portion of eachdrawer 70 (see FIGS. 6B, 7 and 8 ) are sensors or sensor targets,including a proximity sensor target 72 (here a permanent magnet tointeract with a magnetic proximity sensor) and an electronicallyreadable drawer identifier tag 71. In one embodiment, the readableidentifier tag is a passive RFID tag containing an ID which is used touniquely identify the drawer, and to also identify drawer size, (such asby having the first readable alphanumeric character in the stored tagidentifier specify drawer size). One type of proximity sensors areactuatable switches c (such as two position switches), mountedpreferably in the cassette frame, one per compartment. In a switchembodiment, the “proximity sensor target” 72 can be the drawer back. Asshown in FIG. 6B, a single small drawer includes two RFID tags 71 but asingle proximity sensor target (magnet) 72. As a half drawer can belocated in the right side (adjacent to the rear of the cart) or leftside (adjacent to the front of the cart). By placing RFID tags 71 oneach rear side of the half drawer, a half drawer is not sensitive towhether it is positioned in the front or rear portion of the cassette.

When a drawer 70 is installed and closed in a cassette frame 53, therear of the drawer faces the front facing portion of the cassette rearpartition 63. Located on the front facing portion of the partition 63are a series of proximity sensors 62 (such as a hall effect sensor orreed magnetic proximity sensors), with preferably one sensor percompartment, and a series of reading devices 61 to read the drawerelectronic readable identifier (also with at least one device 61 percompartment). In the embodiment shown, the reading devices 61 are RFIDantennas 61, each positioned to interface and read an RFID tag 71 on aclosed drawer 70. The antennas are used in conjunction with a RFIDinterrogation device, such as located on the cassette PCB board e.g.,using a common interrogation device to interrogate a RFID tag via theassociated antenna. In other embodiments, each antenna could beassociated with a separate RFID interrogation device. The devices 61 andproximity sensors 62 communicate status with the system processor viathe communications bus and firmware on the cassette and on the housing.

Each drawer 70 preferably also has at least one latch 69 extendingoutwardly from the drawer’s rear exterior surface, that will couple withcorresponding actuator latches 201 on the interior partition 63 of thecassette, as later described. As shown in FIGS. 6B, 7 and 8 , apreferred drawer latch is a downwardly shaped hooked latch, that willinter-mate with the “U” shaped actuator latch 201 on the rear partition63, for closing and opening a drawer. As the drawers 70 lack handles ora graspable surface, a drawer 70 can be opened only by action of thecart processor 30 or by manual override, later described). To open adrawer 70, the operator will select a drawer 70 to open (the selectionprocess is later described) via one of the cart’s input devices. Theopen command is used to actuate or power one or more actuators 200(generally a servo) associated with the drawer to be opened on thecassette partition 63, which results in a movement of the associatedactuator latches 201 that are coupled to the actuators 200. In oneembodiment, a user enters the open command with a drawer labelidentifier (which can be patient identifier, drawer location, or otheridentifier), and the processor places the drawer open command on thecommunications bus. Each housing receives the command, and determines ifit is directed to a cassette in that housing. The proper housing (viafirmware on the housing PCB) will forward a possibly modify command tothe proper cassette. The cassette (via firmware located on the cassettePCB) will interpret the command, and activate the appropriate latches toopen the proper drawer. In a preferred embodiment, actuator’s (servomotors) move the associated actuator latch 201 first forward, toward thedrawer 70, then downward, toward the floor. The path the actuator latch201 follows during actuation can be controlled by a shape of the linkageconnecting the actuator latch to the actuator, or the linkage can beguided by a shaped structure (such as a channel), or the actuator servoitself may have a shaft that follows an eccentric path, suitably movingthe linkage coupled to the servo shaft. In one embodiment, the actuator200 may communicate its status to a servo manager, (as open, closed, inmotion), such as to the firmware, for use by the system computer oninterrogation.

As the actuator latch 201 moves forward towards the drawer 70, itremains engaged with the drawer latch 61, thereby pushing the drawer 70slightly forward with the forward motion of the actuator latch 201. Thefinal downward movement of the actuator latch 201 allows the actuatorlatch 201 to disengage from the drawer latch, that is, the actuatorlatch “U” shaped hook clears the downward hook portion of the drawerlatch 69, thereby separating the latches and unlocking the drawer,allowing the drawer 70 to be opened by a user. This open action of theactuator latches places the drawer 70 front slightly beyond the frontedge of the corresponding cassette frame 53, such as shown in FIG. 2A.This position of a drawer 70 is termed “almost closed.” In this almostclosed position, drawer 70 is unlatched from the actuator but withinsuch proximity to the actuator that the actuator can retract theactuator, reengage the latches and close the drawer. In the almostclosed position, an operator can grasp the drawer front top edge andslide the drawer fully opened to access the drawer interior. The drawersare slidably positioned or mounted in the cassette frame 53. An openeddrawer 70 is considered any position of the drawer 70 past almost closedposition, providing access to the drawer interior. Until the drawerreaches the almost closed position, it cannot be opened, as the draweris locked, that is, the cassette latch and drawer latch are inter-mated.Medium and large drawers have two drawer latches (such as shown in FIGS.7 and 8 ), and consequently, the system must activate two actuatorlatches simultaneously to unlock and open these size drawers. Hence, thecart must “know” the size of the drawers (which may be contained in theconfiguration map in the computer memory or in memory on the cassettePCB) to allow proper control for opening, closing and locating thesensors that interface with the drawer 70.

In some embodiments, once a drawer 70 is unlocked and positioned in thealmost closed position, the system processor 30 can monitor the periodof time the drawer remains in the unlocked almost closed position, andif a predetermined time is met, the system can reverse the actuatorlatch 201 (e.g., the servo reverses) to close the drawer 70. As shown inthe screen shot of FIG. 14 , the drawer 70 assigned to “Richard Robin”(a patient identifier) has been opened, and the system is tracking theamount of time until the drawer will be automatically closed. To close,the actuator latch 201 will retrace its path, first moving upwardly toreengage the drawer latch 69, then moving in a rearward direction,thereby pulling the almost closed drawer into fully closed and lockedconfiguration; that is, the system automatically closes a drawer. Thesystem processor knows when a drawer has been opened (by tracking thecommand status, or by the proximity sensors). For instance, theproximity sensor can relay status such as “closed” (the drawer is flushwith the cassette frame and locked by the actuator), “open” (the draweris out of range of the proximity sensor) or almost closed as definedherein). Hence the system processor can detect how long a drawer 70 isin the almost closed position, by, for instance, polling the status ofthe proximity, which status may be stored on the PCB board, or directlyqueried based on the poll instruction. In one embodiment, the proximitysensors are used to detect drawer open, closed and almost closedposition. One sequence of steps to open and close a drawer in oneversion of the station (the Medlink lite version) is shown in Table 3.Another sequence of steps to open and close a drawer in a version of thestation (the Medlink Pro version) is shown in Table 4.

Table 3 Drawer Opening - MedLink Lite User action / user display SystemComputer Action 1 In Drawer View, to open a drawer first select thedrawer, either by touching the label in the drawer list or touching onthe drawer in the cassette graphic. In Cassette View, you may also toucha label in the drawer list. (a) Receive open command (b) Find drawerlocation in local table 2 The selected drawer and its label willhighlight in gray, helping you to locate the drawer on the physicaldrawer system. NOTE: With the drawer selected, touch the Open button.From the drawer selected screen, you may also re-label drawers bytouching the Edit Label button. 3 The drawer will unlock ready to beremoved and the cassette graphic will update to show the drawer in blue.The drawer auto close timer will display on screen, along with thedrawer label, (a) Send open command (b) Poll system (c) Update drawerstatus on output screen to show drawer unlocked, update drawer status inlocal table allowing you to confirm which drawer you have opened. If thetimer reaches zero the drawer will automatically relock. You may alsotouch the Lock button to relock the drawer without removing it. With apatient drawer unlocked, touch a storage drawer to first select it, thentouch the Open button to open it. The storage drawer will unlock, andboth drawers will be highlighted blue on the cassette graphic. (d)Initiate timer for auto close (e) Prompt user with notification of timeto auto close (f) Poll status, if drawer status does not change in timeinterval, send close drawer command and update drawer status on screen 4On opening or removing the drawer the display will revert to Drawer Viewwith the drawer list and cassette graphic showing a blank label toindicate there is no drawer present. (a) Poll status, if drawer statuschanges to open (b) Update drawer status on screen and local table 5When the Open All function is enabled, the Open All button is displayedin Drawer View. This allows the user to unlock all the drawers in thatcassette at once. This should only be used when emptying the cassette ofmedication. Opening more than more drawer containing patient medicationwhile administering risks the wrong medication being used. In DrawerView, touch the Open All button to begin the process. (a) Receive openall command, (b) Identify cassette 6 You will be warned that opening allthe drawers should only be done when emptying the cart. Touch OK toacknowledge the warning. (c) Send warning message to screen 7 There areseveral options when opening all the drawers. You may open all thedrawers and retain all the drawer labels, open all the drawers and erasethe patient labels but keeping the storage drawer labels, or erase allthe labels. Touch an option to continue. (a) Receive option from user,execute selected option (modify information in local table on drawers) 8All the drawers on the chosen cassette will unlock and highlight in blueon the cassette graphic. Drawers may be removed and emptied. If drawersare not opened or removed, when the re-lock timer reaches zero, theywill automatically re-lock. (a) Receive open all command, (b) Send openall command to housing with cassette address 9 If you selected an optionsuch as “Open all & Erase all labels” the appropriate labels will bemissing when the drawers are replaced. Execute option is selected

Table 4 Drawer Opening - MedLink Pro User action / user display SystemComputer Action 1 When you are with the patient and ready to administermedication, scan the patient’s wristband bar code. Ensure the MedLinkwindow is in the currently active window, otherwise the bar code scaninput will not reach the MedLink software. (a) Receive scanned bar code,(b) Retrieve RFID information associated with patient from the server,based on patient barcode (c) Locate drawer(s) in cart (housing, cassetteand compartment) (d) Verify user credentials for authorization to opendrawer(s) 2 If drawer(s) assigned to that patient are detected in thecart, the drawer(s) will automatically unlock. The screen will displaythe auto close timer. If no further action is taken at this point, thedrawer will relock, securing the medication. (a) If user authorized anddrawer(s) located, send open drawer command on bus (b) Poll systemstatus (c) Update drawer status on output screen to show drawerunlocked, update drawer status in local table (d) Initiate timer forauto close (e) Prompting user with notification of time to auto close(f) Poll status, if the drawer(s) status does not change in timedinterval, send close drawer command on bus, and update drawer status onscreen as closed (g) If drawer(s) are removed, auto close timer closes.3 If a bar code is damaged or unavailable to scan and you need to accessa drawer, begin by selecting a drawer and clicking the Open button. Onthe following screen where you are prompted to scan a bar code tocontinue, click the Cannot Scan barcode button. You will be prompted toenter the login credentials of a colleague or to enter the patient’s PANor MRN number to record that you are opening a drawer without thesecurity of scanning a bar code. Once the credentials have beenaccepted, on the next screen enter the reason you cannot scan theappropriate bar code. On clicking Continue, the drawer will unlock andyou can continue to fill or administer medication as needed. (a) Systemreceived request to open drawer without a location bar code scan.Displays screen informing user of needed scan with option for manualoverride. User selects “Cannot scan bar code” button. (b) System showspreconfigured screen (either witness override or PAN/MRN override). (c)System obscures PAN/MRN if shown on center screen. (d) System validateswitness credentials or PAN/MRN to server. (e) If credentials pass systemwill display Reason screen asking for the reason (if configured) (f)System will then send command on bus to open the selected drawer. (g)System will display auto close timer 4 Pull the drawer out and remove itcompletely if you wish. The screen will update, indicating the drawerhas been removed. At this point you can go ahead with your normalmedication administration process. (a) If drawer status changes duringtime interval, (eg. to open or closed) - refresh screen to reflect newdrawer status and store new drawer status in server table 5 With apatient drawer(s) open, you may also open a storage drawer(s) to accesssupplies and consumables needed to administer the medication. Simplyclick on a storage drawer to unlock it. (a) Receive user input to openstorage drawer (b) Verify user is allowed to access storage drawer(server database) (c) Locate storage drawer in cart (housing, cassettecompartment) (d) If user is authorized and drawer located, send opendrawer command on bus (e) Poll system status (f) Update drawer status onoutput screen to show drawer unlocked (g) If drawer status changes,refresh screen to reflect new drawer status 6 As long as a patientdrawer is open, the on-screen prompt will remain, advising the user toreturn the patient drawer to continue. This ensures that only onepatient drawer may be opened at a time, thereby preventing thepossibility of medication getting mixed between patient drawers. Asingle patient may have more than one drawer assigned. All assigneddrawers to a single patient will open on wrist band scan. 7 When thepatient drawer(s) are returned to the cassette, the process ends and thescreen returns to the home screen. (a) Poll status (b) Detect drawer,update screen with received identifiers, update status on screen and inserver table (c) If drawer status non-retracted, initiate timer for autoclose (d) Prompt user with notification of time to auto close (e) Pollstatus, if drawer status does not change in time interval, send closedrawer(s) (f) Command on bus, and update drawer status on screen (willclose all unlocked drawers) 8 Storage drawers may be unlocked at anytime without scanning a bar code by clicking on the drawer, and thenclicking the Open button. Note: Storage drawers may be configured tounlock automatically with patient drawer(s) or on login. (a) Systemsends command on bus to selected storage drawer.

In operation, the system “knows” the identity, size and location ofevery drawer in the cart. In one embodiment, each drawer has at leastone unique identifier established in the RFID tag 71, and that tag isreadable by an RFID reader/antenna 61 positioned on the cassette rearpartition 63. When the drawer 70 is closed, the RFID antenna 61 ispositioned adjacent to the drawer RFID tag 71, allowing the RFID readerto interrogate the RFID tag 71, receive the stored information andcommunicate the stored information to the system processor for use. EachRFID reader or antenna 61 has a unique location on a cassette 50, andcan be electronically addressable by the system processor to initiate aquery of the associated RFID tag. The system processor may request theRFID reader to query the RFID tag on a drawer. Once a RFID tag is read,the processor knows or can determine which drawer location(s) isassociated with the tag that was read. Armed with this information, andthe information on drawer size from the RFID tag, the system candetermine the configuration of the drawers in the cassette (e.g., queryeach antenna for information, and map the responses). Consequently, thesystem (via the processor and software and computer memory) knows whatdrawers 70 are present in each cassette 50 in the cart 10, the specificlocation of each drawer 70 in each cassette 50, the size of the drawer70, and in some embodiments, may have stored the RFID information oradditional sensor or actuator addresses associated with each drawer inthe cassette 50. The configuration of the station (number of housings,number of cassettes in each housing, and the identity of the drawers ineach cassette, such as patient identifier) is preferably stored in theassociated system memory (either local and/or remote on a server) aspart of the database configuration map describing the stationconfiguration. The station configuration can be displayed on the systemdisplay device (such as a GUI interface) as a visual map of the cart’scassettes, for use by an operator. In certain embodiments, the storedconfiguration information is limited, and consequently, theconfiguration map displayed will be limited.

At designated intervals or alternatively, on designated events (e.g.,drawer closing), the system processor will interrogate or poll a draweror the equipment to verify/update the system configuration. Forinstance, if a cassette has been removed, the system knows the cassettehas been removed (from the ejection sequence, and in some embodiments,from a sensor reading (such as a switch output)). If a cassette has beenrecently installed, that event can trigger an interrogation sequence ofall RFID antennas 61. In this event, the system processor caninterrogate the newly installed cassette to determine the identity ofthe drawers in that cassette, and update the configuration map with thenew drawer identifiers, sizes and locations. For instance, in a serverembodiment, the system processor can determine the RFID tag informationin an installed cassette, pass the RFID information to the server, anddownload the patient identifiers stored in the server to repopulate theconfiguration map to be displayed on the cart’s display device. In aserver embodiment, multiple stations may have drawer information storedon the server memory (and the server may also have a cart or cassetteidentifier stored and associated with each station/cassette). In thisfashion, the system updates its configuration data to stay current.

Once a drawer 70 is fully opened, the system generally losescommunication with the drawer 70, as the RFID tag 71 and magnet 72 aretoo remote from the RFID reader/antenna 61 and proximity sensor 62 forinteraction with the associated sensors. On closing of a drawer 70, thesystem may confirm/update the identity of the drawer 70, and if a drawer70 has been swapped out with another drawer 70, update the configurationmap with the new drawer data and may download the associated patientidentifiers from the server, or a HIS system, later described. Thedisplay device generally will indicate that the drawer is open when adrawer has been opened or removed, reflecting the status of the drawer.Preferably, if a patient drawer 70 is opened, the system will not allowa second patient drawer to be opened (absent, for instance, an overridecommand, administrator access, or pharmacy access, for instance, wherean “open all drawers” command may be utilized).

The control of the drawers is undertaken by users interacting with thesystem software via the system input devices. The system softwaregenerally provides for a “System Administrator” user, such as asupervising nurse, to log into the system and configure the system. Ingeneral, only one user may be logged into and controlling a station atany given time, however, the cart may be configured to accommodatemultiple users, logged on at different times. Configuration of thesystem for multiple users is preferably undertaken by the SystemAdministrator. Other configuration actions are preferably undertaken bythe System Administrator, or another user that has been granted accessto such actions by a System Administrator. For instance, when the cartis shared among users, specific configurations can be associated foreach UserID, or groups of UserIDs, to customize cart operation accordingto each user or user group preferences. For instance, certain UserIDsmay only be provided access to designated drawers having specificidentifiers (such as ward identifiers), or only provided access to thesystem at designated locations. The System Administrator or otherproperly credentialed user, can provide different rights to thedifferent users, or different groups of users, and store these accessrights, or group rights, in system memory (generally local cart memory).Once logged in, a user may be denied access to certain cartfunctionality, such as denied access to certain drawers, denied theability to eject cassettes, or denied other station functionality. Forinstance, a particular user group may be denied or granted rights toopen all drawers at one time. The system, as described, is highlyconfigurable.

Additional information (patient identifiers) may be associated withspecific drawers in system or server memory. For instance, a particulardrawer may be assigned to a particular patient. To assign a patientidentifier to a drawer 70, a properly credentialed user (granted theright to assign drawers) selects the drawer to assign (the user mayfirst have to select the cassette on which the drawer is to be assignedin some versions), and then activate the assign function from the inputdevice. See the screen shot of FIG. 13 . The user may select a drawer byclicking on an image of a drawer, or touching an image from a touchscreen input, or inputting a specified drawer identifier (such as A1,A2, A3, A4). By activating the assign command, the user can then inputadditional information to be associated with the drawer in theconfiguration map (and replace previously stored information), such aspatient ID, patient DOB, ward location, patient bar code or hash codeidentifier, location identifier (e.g., patient room), location bar codeor hash code identifier, or other pertinent information. In someembodiments, multiple patient identifiers can be associated with aparticular drawer, such as patient ID, bar code, location, etc. Oncestored, designated identified characteristics, such as patient name, canbe displayed on the system display device. The information displayed, insome embodiments, can be controlled via system configuration by theSystem Administrator. These patient identifiers may be transmitted andstored on a local or remote memory (a server database).

For instance, shown in the screenshot depicted in FIG. 12 , is theconfiguration of a particular cart containing three cassettes. In onecassette, certain drawers (reference 124) are associated with specificpatients, while one drawer is not assigned. In a second cassette,certain drawers (references 125) are associated with specific patients,one drawer is identified as a storage drawer, and one drawer is notassigned. In the third cassette, all drawers (references 126) areassigned to specific patients.

A drawer can also be assigned as a “common” supply drawer, where varioussupplies will be located that may be applicable to multiple patients ona given distribution workflow. From the assign/re-assign screen orcommand, stored drawer parameters can be edited, modified, or deleted,or a drawer de-assigned (wipe all identifiers) or reassigned. In someembodiments, to reassign a drawer, the system may require the user tohave Administrator status. The complete set of patient identifiersassociated with a specific drawer may also be viewed, for instance, viathe assign command. Generally, the cassette components identified with aparticular drawer (or the addresses of these components, such asactuators, and sensors) are generally not displayed for a user, as thereis little need for such by the user - these identifiers are used by thestation during station functions (open drawer, close drawers,interrogate status, etc.). One sequence of steps to assign a drawer forone version of the station (the Medlink Lite version) is shown in Table5. One sequence of steps to assign a drawer in another version of thestation (the Medlink Pro version) is shown in Table 6.

Table 5 Drawer Assignment/Labeling - MedLink Lite User action / userdisplay System Computer Action 1 In order to label a drawer to store apatient’s medication, go to Drawer View for the cassette you wish touse. In the list on the right-hand portion of the display, touch the AddLabel icon that corresponds to the drawer you wish to label. (a) Receiverequest to add label 2 You will be presented with a list of options forlabelling the drawer. Touch “Enter drawer label”. To label a drawer as astorage drawer instead of a patient drawer, touch “Label drawer asSTORAGE”. (a) Refresh screen with add label options (b) Receive usersoption selection 3 This will take you to the label entry screen. Use theonscreen keyboard to enter an appropriate label. You might want to useto the patient’s last name, both first and last names, or room numberfor example, or a descriptive label if you are labelling a storagedrawer. There are no restrictions on the text you may enter. When youare done entering the label touch the Save button. (a) Refresh screenwith labelling options (b) Accept user input, update local table withentered label information (local table contains RFID information andstored label information) 4 The display will return to Drawer View andif successful, you will see that the list shows the new label youentered, and the corresponding drawer on the cassette graphic ishighlighted in bold. If you labelled a drawer as a storage drawer, youwill see the drawer in the drawer list and on the cassette graphic isrepresented by being underlined and having uppercase text. This is tovisually differentiate storage drawers and prevent you mistaking themfor a drawer containing patient medication. (a) Refresh screen,displaying new label information 5 On returning to Cassette View youwill see the new drawer label is shown in the list, and the cassettethat contains the drawer is highlighted bold.

Table 6 Drawer Assignment/Labeling - MedLink Pro User action / userdisplay System Computer Action 1 Ensure you are near to your AutomatedDispensing Cabinet or in your medication store room and have access tothe MedLink location bar code. On logging in to the software you will bepresented with the home screen. (a) System validates user credentials onserver (b) If user validated, system shows home screen 2 Scan thelocation bar code as prompted to tell the system you are in a designatedlocation for assigning and filling drawers. (a) Receive bar code, verifylocation from server as appropriate for desired actions (b) Verifycredentials of user for ability to change drawer assignments 3 When thelocation bar code is successfully scanning, the center icon will changeto blue. Click on screen on a currently unassigned drawer that you wishto assign to a patient. (a) System displays Action screen for choosingassignment type (b) Receive request to assign a drawer (c) Locate draweridentifier in server table and recover RFID 4 The selected drawer willhighlight in blue and the center prompt area will change, giving you thechoice of assigning this drawer to a patient, storage or an unassigneddrawer. Click the Patient button, or Click on the Storage button Clickon the Unassign button (a) If assignment function is invoked, updatescreen to show assignment options 5 The screen will now display a listof patients, within the hospital than can selected an assigned to thedrawer. By default, the list shows only patients from the current user’sdepartment. The list may be expanded using the drop down menu to includepatients from all departments, or patients from a different department.The list may be searched using the text box. If the patient is not foundin the list, a drawer mat be manually labelled using the button in thetop right. Note that when using this option, drawers do not display anyinformation other than the label you enter, and it will not be possibleto open the drawer using patient wristband scanning, since there willnot be a wristband bar code associated with the drawer. If you selectedStorage, the screen will allow you to enter a label for the storagedrawer. Enter a label and click the Save button. Auto selection (a) Ifpatient assignment is requested by user, retrieve patient informationfrom the server database and display on screen Note: hospitalinformation system (HIS) is inserted into the server database as ithappens. Manual selection (a) Display selection parameters on screen foreither Patient or Storage drawer 6 Select your chose patient and thenclick the Assign button. If you entered a Storage label or Patient Name,click Save. Auto selection (a) Receive patient selection from serverdatabase (b) See table 16B for drawer open sequence. Drawer to beassigned must be removed before assignment can continue. Manualselection (a) Accept identifiers for drawer, send patientidentifiers/drawer identifier to server to update records. (b) See table16B for drawer open sequence. 7 Fill the drawer with that patient’smedication and return the drawer to the cassette as prompted, ensuringit locks into place. (a) See FIG. 16B for close drawer function. 8 Youwill be returned to the home screen, and on screen the selected drawerwill now show the details of the patient you chose, or the storage labelyou entered. The assigning and filling process is now complete.

In some embodiments (the Lite embodiment, for instance, depicted in FIG.11 ), the display device may display a picture of the current installedcassettes, and once a cassette is selected by the user, display drawerconfigurations for the selected cassette alone (such as using a zoomfeature, to allow a user to zoom in or view only the informationassociated with the selected cassette and to interact with the selectedcassette). This feature is useful if screen size on the display deviceis limited (for instance, in a wireless environment, a cart may bemonitored remotely by, for instance, a ward nurse via a handheld tablet,or via an application on a smart phone). In a small screen displayembodiment, displayed drawer information may be limited to drawerstandard identifiers (without patient identifiers), such as drawer A1,or B2, such as where the letter (A, B, C, or D) reflects cassetteidentifier, and the number (1-8) reflects compartment identifier in thecassette). Alternatively, drawers may be displayed for selection by alist. Preferably, in most embodiments, the system’s display output isconfigurable.

In other embodiments, patient data may be downloaded into the systemmemory from the hospitals information system (HIS) network (connectedvia a wireless connection between the system and HIS, for instance,similarly to the system in a client/server embodiment). To assign adrawer, the user selects a drawer, then requests a list of patients fromthe HIS, and the system displays the list received from the HIS on thecart display device. The user could select the patient to be assignedfrom the displayed list (e.g., mouse click on the selected patient, ortouch the screen in a touch screen environment), and the system wouldthen request the HIS to transmit certain of the patient’s information(e.g., DOB, patient bracelet bar code; patient room, etc.). The systemprocessor would receive the information and associate the patientinformation with the drawer and enter this information in theconfiguration map with the selected drawer (and, for instance retransmitthe information to the server, if present). The cart can utilize the HL7integration to access the patient-related information stored on HIS.Interfacing of the cart with the hospital’s information system can beachieved using currently available software. Alternatively, the usercould scan a patient’s identifier, or enter a patient ID, and have thesystem query the HIS system (or server in some embodiment) for otherpatient information.

To open a drawer, the user selects the drawer to open (again, in someembodiments, select cassette first). The selection can be undertaken byvarious procedures, depending on the cart’s configuration and thepreferences of the particular user (UserID), the system capabilities, orconfigurations established at the work location. For instance, in oneembodiment, the user scans the patient bar code bracelet with a bar codereader located on the cart (see, for instance the screenshot of FIG. 12). The scanned ID is then compared with stored information to see if adrawer on the cart has a matching patient ID associated. If so, thesystem would identify the drawer location in the cart, and actuate theactuator latches associated with the drawer location (accomplished inconjunction with the firmware on the system). This operation allows theselected drawer to move to the almost closed position to allow the userto grasp the front of the drawer and pull it fully open. Once opened,the nurse can interact with the drawer contents - load the drawer,remove prescriptions from the drawer, etc.

In other embodiments, the nurse may indicate which drawer to open, forinstance selecting from a list displayed on the display device, orselecting from a displayed map of a cassette by touching the drawer onthe displayed map of the cassette configuration, in a touch screenenvironment, or entering a drawer number (for instance “AS”) in an inputdevice. The input may be via keyboard, mouse, touch screen or otherinput device. Once the drawer is identified, the system, activates theactuators associated with the drawer, to unlock and move the drawer tothe almost closed position.

In some embodiments, all drawers may be selected to be opened (orclosed) at one time. The selection can be made on entry of a specific“open all” command, or, for instance, by entry of a specific locationcode (such as the pharmacy location code). In some embodiments, onlydrawers associated with a particular identifier may be opened at anygiven time, to provide for secure distribution of medication. Forinstance, all drawers for a given user group or patient could be openedat once for a common distribution at a nursing station.

In a preferred embodiment, if a particular patient’s associated draweris opened, another patient’s drawers (e.g., assigned to a differentpatient) on the cart may not be opened concurrently. In otherembodiments, a drawer identified as a common supply drawer may be openedwhile any other drawer is opened. In other embodiments, a supply drawermay be associated with a set of specific patients (or a subset of otherdrawers), and only opened when the associated patient’s drawer isselected. As described, the system is flexible, allowing the user toconfigure a subset of drawers that can be opened concurrently, based onuser supplied parameters.

As described, the drawers 70 in a cassette 50 can be opened from thecart processor. In other embodiments, the cassette 50 may be removedfrom a cart, and transported to a remote location and inserted into aremote cart or docking station (such as a fixed station located in thepharmacy area) for filling or emptying of the drawers. A docking stationcan be another cart, or fixed cart (not movable), where the cassette canbe inserted into a housing 90. For a fixed docking station, the housing90 may be dispensed with, and a simple communications plug, coupled tothe cassettes' firmware to exercise control /communication with thecassette drawers, could be used. Preferably, the docking station has adisplay device and input device to display and/or modify theconfiguration of the docked cassette.

To close a drawer, different procedures can be used depending on systemconfiguration and the equipment configuration. In some embodiments, theuser may simply push the drawer back into the drawer slot until theactuator latch(es) 201 hook portion contacts the drawer latch(es) 69,and on further rearward movement rearward, two latches are positioned inan inter-mating latched relationship, thereby latching or locking thedrawer in a closed position. In other embodiments, the operator may pushthe drawer 70 into the drawer slot until the drawer is in the almostclosed configuration. Then the system processor, on detecting the drawer70 (via proximity sensor 62), will (in conjunction with the firmware inthe cassette) activate the actuators 200 associated with the drawerafter a predetermined time (which can be set by the SystemAdministrator), allowing the actuator latch 201 to pivot upwardly andre-engage the drawer latch 69, then pulling the drawer 70 into a closed,latched configuration. In other embodiments, the user may activate aclose drawer command, possibly after selection (or before selection) ofthe drawer 70 to be closed, and the system would then cause theappropriate actuator(s) 200 to operate (for instance, in reverse) toallow the associated actuator latches 201 to re-engage latches 69 toclose and lock the drawer. In other embodiments, the system may allowfor a command to close all drawers, allowing activation of all actuatorsat substantially the same time (or two latches at a time to reduce thepower draw on the system’s battery).

In a preferred embodiment, the system software may interface with thehospital’s information system (HIS) network. Generally, for thisfunctionality, the cart’s computer system will have wirelesscommunication capability, but a hardwired interface with the processorcan also be used (such as via Ethernet cable) to interface with the HIS.If the system includes a laptop, preferably the laptop has wirelesscapability. One benefit of interfacing with the HIS is that each cart 10can exchange information with the HIS, similar to the exchange in aclient/server embodiment. For instance, if a particular drawer 70 hasbeen assigned to a particular patient, the patient information can bedownloaded to the system from the HIS for population of the patientidentifiers (DOB, Bracelet number, etc). Alternatively, in someembodiments, drawer information can be communicated to the HIS andstored in the HIS system, such as cart identity or name, drawer identity(such as drawer unique RFID) and some of all patient identifiers. Whenthe drawer is removed from one cart and positioned in a second cart, thesecond cart could query the HIS system for stored drawer assignedinformation (based on providing drawer RFID identifiers to the HIS andrequesting transmission of associated patient identifiers), and receivethe stored patient identifiers from the HIS. This allows drawers to bemoved from cart to cart (or to a remote loading docking station) withoutthe need to manually enter drawer assignments or drawer patientconfigurations. Once communication between a cart and the HIS isenabled, patient information can be shared between the cart and HISusing, for instance HL7 protocol. The sequence of steps in Table 6 alsodepicts populating patient identifiers from remote computer memory, suchas the server memory in a client/server embodiment of the station, orthe HIS system memory.

The cart can also store cart or drawer activity, either in local memory,server memory, or in other embodiments, to transmit activity informationto the HIS, in order to run reports of cart usage (user usage), draweractivity, and other relevant statistics. Reports may be compiled fromthe cart system, or in other embodiments, from the server or HIS withsuitable software in the HIS and server. In one embodiment, onceinstalled in the cart, the processor may inform the HIS of the drawer’spresent location, for tracking of the drawer history. The cart canutilize the HL7 protocol to access the patient-related informationstored on the HIS. This interfacing of the cart with the hospital systemcan be achieved using currently available software.

The cart system includes manual overrides to allow a cassette to beremoved or ejected, and for the drawers to be opened, for instance, inthe event of a power failure. For instance, one manual override for alockable cassette handle is to have the handle lock activated by amanual hardware key on the housing for manual removal of a cassette froma housing. A similar hardware key could also be used on the cassette, tomanually unlatch all of the activator latches (via a linkage systemcoupled to the lock) to allow all drawers (e.g., manually actuate alleight activator latches) to open. For instance, manual activation may beneeded in the event of a power failure, or when the cassette istransported outside of the housing and thus not in electricalcommunication with the cart.

On initial set up, the System Administrator sets up and configures eachcart, that is, the administrator can initialize the data fields andconfigure the system as desired, set up the user ids/passwords, assignthe cart an identity or reference code (if it is to network into thehospital system (e.g., client identifier for use in a client/serversystem)), establish user groups to control access to the drawers forrefilling; identify and label drawer information fields to be associatedwith each drawer and RFID tag (patient bar code; room ID; DOB, etc.).The staff may also initialize the drawers by assigning patient values oridentifiers to them, particularly when the system networks into the HIS,such as by choosing a patient to be assigned to a drawer, preferablyfrom a list received from the HIS system, and receiving the patientidentifiers (such as from the HIS system) and populating the appropriatedata fields for display on the cart. The staff may identify some drawersas a common supply drawer; identify relevant location codes (pharmacy orADC location, patient room code, etc.) as needed.

Once the cart/cassettes are set up and configured to associate aspecific patient with one or more RFID tags (or other electronicidentifier, such as a bar code) on the various drawers, the cart systemcan be used. The user takes the cart (or just the cassette) to the ADC,and can open all drawers in a cassette (possibly after scanning in thelocation code of the ADC or pharmacy) and the system may display apicture showing drawer locations and drawer identifiers, to allow theuser to properly open and fill the drawers with medications as neededfor each patient, and for the common supply drawer if one is assigned.Alternatively, the user can open each drawer individually andsequentially to fill the drawers using the configuration map displayedon the visual display device.

Once the cart is loaded, the user will move the cart to the firstlocation on his/her distribution workflow route, and for each patient atthat first location; open that patient’s drawer(s) (such as by enteringthe patient ID or scanning the patient’s wristband with bar codereader), distributing the proper drawer contents, and closing thedrawer. The user then moves the cart to the next patient location fordistribution. This process continues at the second location, and thenrepeats until all patients at a specific area (such as a ward) areserved. The user will then move the cart to the next location, andrepeat the process.

One particular embodiment of the invention is shown in FIG. 11 ,sometimes referred to as the T7 MedLink Lite or MedLink Lite embodiment(“Lite”). This embodiment uses a T7 cart, but does not necessarilyinclude a separate monitor, keyboard, or laptop. Instead, a tablet, suchas the computer tablet built into the T7 work surface may function asthe system processor, and memory display and input device (a touchscreen). Additional devices may be coupled to the tablet, such as amouse or scanner. In the Lite version, the cassette’s drawers areconfigured with RFID tags, but proximity sensors are not necessarilyneeded, unless the Lite embodiment is to be configured for automaticdoor closure (the sensors may be included, but auto closing functioningmay be disabled by the System Administrator). The Lite system can bedesigned for a single user, so access in this instance is generally by aPIN number or other access code means known to those of ordinary skillin the art. Once the user is logged into the system, the user can openany drawer, or all drawers, by using the touch screen on the tablet toselect the drawer(s) to open. In general, the Lite version may only uselimited patient identifiers, and is usually not used in a client/servermode. The Lite version is also generally not configured to interfacewith the hospital’s information system network, and thus moving a drawerfrom one cart to another requires reentry of drawer identifiers in thenew cart.

Another particular embodiment is referred to as the T7 MedLink Proversion, such as shown in FIG. 1 . In this embodiment, a separatemonitor is used as the primary display device, and input devices caninclude a keyboard, mouse and bar or hash code scanner. The systemprocessor includes a laptop located on the cart, but the cart’s computersystem may also be configured with wireless interaction with thehospital’s network system and a system server. Consequently, certain ofthe system’s software functionality can be running on the hospitalserver or system server (such as the report generation capability). Thepreferred T7 cart includes a tablet that controls cart heightadjustment, but operation of the cassette functionality in the MedLinkPro version, and interaction with the cassette equipment (proximitysensors, latches, RFID) will normally occur from the cart processor, notthe T7 tablet. The Pro version is designed to accommodate multipleUserID/passwords and includes the ability to generate detailed reportson the use of the system, such as UserID usage, patient usage, drawerhistory, etc. In the MedLink Pro system, all drawers may not beaccessible to all users, as some drawers may be assigned to specificUserIDs or user groups. The drawers preferably auto close, and can beopened by selecting a drawer associated patient identifier throughinteraction with the software, or preferably, by scanning a patient’swristband, where the patient wristband code is associated with aparticular drawer or drawers in the configuration map. Multipleidentifiers or information items can be associated with each assigneddrawer.

Other embodiments of the medical cart may have at least two protectionlayers for drawers that might contain Schedule II controlled substances.The two or more layer protection may include two layers of security,including one or more locking mechanisms, one or more digitalauthorization requirements (dual factor authorization), and may requireone or more people involved in the authorization process. Theauthorization process can include a combination of personnel, logicalprocesses, authorizations, physical devices or electronic lockingprotection. Alternatively, a special narcotics cassette drawer orcassette housing could be used to accommodate narcotics.

For instance, if a drawer is to contain heavily regulated narcotics,that drawer could have an additional patient identifier indicating that“narcotics” are contained in the drawer. This identifier could bemanually input by the user during operation, or the identifier could beembedded into the RFID tag such that unique RFID tags are used fornarcotics drawers. For example, a “narcotics” drawer may be identifiedas such by the drawer identifier and recognizable as such by reading theidentifier (a narcotics drawer may have an identifier that starts with adesignated alpha-numeric character), or by receiving the drawer statusas a “narcotics” drawer from the server computer. This “narcotics”identifier would indicate to the cart that dual layer protection or duallayer authorization is required to open this particular drawer,requiring a second authorization tool be deployed. For instance, asecond password or PIN may be required to access the drawer; the systemcould require the user to verify the user’s identify by requiring theuser to meet a second identification or credential test, such asfingertip scan, retinal scan, voice identifier or other biometric scan,or to require the user to have a physical authorization identifier orreadable token present (such as a RFID tag with a readable UserID, anurse id bracelet with bar code or a hash id that can be scanned by thesystem; a fob, a badge reader, or other device, such as a digitalcertificate stored on a smart phone, or a readable card or USB token).The token must be present (e.g., detectable) by the system before accessis granted. These tokens or biometric tokens may be held by the sameperson, or by different persons such that two or more users need to bepresent to access the narcotics drawer. Alternatively, the system mayemploy two factor authentication, where the system sends an electronicauthorization code to the user’s electronic account (such as that user’ssmart device or hospital email account), and that user has to receivethis dynamically assigned authorization code and then enter thisauthorization code into the cart to provide access.

Dual layer physical electronic/mechanical protection may also be used.For instance, a “narcotics ” drawer may have a second physical layer ofprotection, such as a separate lock (electronic or physical lock, suchas a keyed lock) requiring the user to have the key to the second lock.Alternatively, the cassettes could have one or more additionalseparately actuatable latches that are used for narcotics drawers,requiring a two-step unlatching sequence before access is provided. Thissecond latch layer can be combined with separate authorization, e.g.,the additional one or more latches is only actuatable by a secondproperly credentialed user. For a narcotics drawer, the second one ormore latches would not open the drawer, but would simply unlock to allowthe second one or more mechanical latches to open the drawer. Forexample, the second latch or latches would unlock first, therebyallowing the first latch or latches described above to unlock andpartially open the narcotics drawer. In a dual latching layer system, aseparate cassette may be used with all drawers labeled as narcoticsdrawers, with the cassette backplane and cassette firmware modified toaccommodate separate latches. In one embodiment, a similar spring-loadedlatch that is used for the ejectable handle for the cassette could beused for the second latching mechanism. The cassette identifier could belabeled as a “narcotics” cassette to allow a cart to recognize thiscassette and all drawers as “narcotics”, and to required dualauthorization as specified in the system. The separate cassette could besituated beneath the non-narcotics housing(s) and could be incommunication with the computer system in the same manner as thenon-narcotics housing(s). The foregoing description and accompanyingdrawings illustrate the principles, exemplary embodiments, and modes ofoperation of the invention. However, the invention should not beconstrued as being limited to the particular embodiments discussedabove. Many modifications of the embodiments described herein will cometo mind to one skilled in the art having the benefit of the teachingpresented in the foregoing descriptions and the associated drawings. Forinstance, the RFID tags may be replaced with a bar code or hash code,and the RFID reader replaced with a scanner; the proximity sensor may bea capacitance sensor, photo sensor, optical sensor, ultrasonic sensor,or other type of proximity sensor. Instead of addressable electroniccommunications on a common bus or common communications path, eachperipheral sensor or device could have a dedicated communications path,eliminating the need for an addressing scheme and a common bus, butincreasing the wiring harness size. As used herein, “electroniccommunication” encompasses both common bus communication and dedicatedindividual communications path, or a combination thereof. The station isgenerally described as a movable cart, however the station may be afixed station, such as a docking station used in a fixed locationdescribed above. Further, in the system as described, the cassettecomponents respond after being polled by the processor. Alternativecommunications schemes are included in the scope of the invention, suchas using an interrupt request by the peripheral devices to establishcommunications. Accordingly, it should be appreciated that variations tothose embodiments can be made by those skilled in the art withoutdeparting from the scope of the invention.

What is claimed is:
 1. A medical station comprising: a movable cart; acomputer system comprising an input device, a display device, and aprocessor, the computer system positioned on the cart and includingcomputer memory in communication with the processor; a housing mountedon the cart; at least one portable cassette system removably coupled tothe housing, wherein the processor is in electronic communication withthe input device, the display device, and the cassette system; andwherein the cassette system comprises: a cassette frame defining aninterior divided into compartments; drawers, each of the drawersoccupying, and being slidably positioned in, at least one of thecompartments; each of the compartments having an actuator associatedtherewith in communication with the processor and associated with anactuator latch that is movable in response to operation of theassociated actuator; each of the drawers having at least one drawerlatch, and each of the drawers capable of moving from a locked andclosed position to an unlocked position in response to movement from theassociated actuator latch, a drawer manual override configured to allowa hardware key to mechanically unlatch all of the actuator latches sothat the drawers are capable of opening.
 2. The medical station of claim1, wherein: the housing includes a cassette manual override allowing thecassette system to be mechanically unlocked and removed from thehousing.
 3. The medical station of claim 2, wherein: the cassette manualoverride includes a locking device manually actuated by a hardware key.4. The medical station of claim 2, wherein: the cassette manual overrideincludes a lockable cassette handle activated by a manual hardware key.5. The medical station of claim 1, wherein: the computer system isconfigured to automatically transition a specific one of the drawersfrom the unlocked position to the locked position where the specific oneof the drawers remains in the unlocked position for at least a selectedperiod of time.
 6. The medical station of claim 1, wherein: the computersystem is configured to move the specific one of the drawers into theunlocked position by movement of the actuator associated with thespecific one of the drawers in response to receipt of an open drawercommand for the predetermined one of the drawers received from the inputdevice; and the computer system is configured to, in response to adrawer open command, the actuator associated with a specific one of thedrawers actuates to move the actuator latch of the specific one or thedrawers from the locked and closed position to an unlocked and almostclosed position.
 7. The medical station of claim 1, further comprising:a series of proximity sensors each in electrical communication with theprocessor, each of the drawers being associated with one of the seriesof proximity sensors.
 8. The medical station of claim 7, wherein: thecomputer system is configured to detect whether each of the drawers isin a closed position or an almost closed position based on output of theproximity sensors.
 9. The medical station of claim 7, furthercomprising: electronically readable identifier tags, each associatedwith one of the drawers and comprising a unique drawer identifier,wherein said series of proximity sensors comprise electronic readers,each associated with one of the drawers and configured to read theidentifier tags, wherein the computer system is configured to identify aposition of each of the drawers in the cassette frame based on positionsof the electronic readers relative to the unique identifiers for thedrawers.
 10. The medical station of claim 9, wherein: each of theidentifier tags comprise a radio frequency identifier (RFID) tag. 11.The medical station of claim 10, wherein: each of the RFID tags alsoindicate a number of the compartments occupied by an associated one ofthe drawers.
 12. The medical station of claim 7, wherein: the computersystem is configured to classify a respective one of the drawers as inan open position when the proximity sensor associated with therespective one of the drawers is not detected; the electronic readersare capable of reading the RFID tag of a first one of the drawers whichis in a closed position, but are not capable of reading the RFID tag ofan adjacent one of the drawers when the adjacent one of the drawers isin the closed position; and the electronic readers are configured toread only the RFID tag of the first one of the drawers by way of a l owpower signal which is incapable of energizing the RFID tag of theadjacent one of the drawers.
 13. The medical station of claim 1,wherein: the computer system is configured to prevent a second one ofthe drawers from movement into an opened position when a first one ofthe drawers is in the opened position, unless the computer systemreceives at least one of an override command, an administrator accesscommand, or a pharmacy access command.
 14. The medical station of claim1, wherein: the cassette system further comprises: a spring-loadedgraspable handle slidably mounted on the cassette frame for movementbetween a closed position where the handle is not accessible orgraspable by a user and a released position; and a handle actuatormounted to the housing for moving the handle between the closed positionand the released position.
 15. The medical station of claim 1, wherein:said computer system comprises a configuration map located in thecomputer memory, the configuration map comprising, for each respectiveone of the drawers, a unique drawer identifier and an indicator of alocation of the respective one of the drawers in an interior of thecassette frame.
 16. A medical station comprising: a movable cart; acassette system provided at said moveable cart and comprising: a frame;a plurality of drawers slidably mounted to said frame; a plurality ofcompartments defined by said frame, each occupied by one of saidplurality of drawers; a plurality of actuator latches, each associatedwith one of the plurality of drawers; a drawer manual overrideconfigured to accept a hardware key and mechanically unlatch all of theplurality of actuator latches so that all of the plurality of drawersare capable of opening upon insertion of said hardware key and actuationof said drawer manual override.
 17. The medical station of claim 16,wherein: the housing includes a cassette manual override allowing thecassette system to be mechanically unlocked and removed from thehousing; and the cassette manual override includes a locking deviceconfigured for manual operation by a hardware key.
 18. A medical stationcomprising: a movable cart; a cassette system provided at said moveablecart and comprising: a housing; a plurality of lockable drawers slidablymounted to the housing; a drawer manual override configured to unlockall of the drawers so that the drawers are capable of opening uponactuation with a hardware key.
 19. The medical station of claim 18wherein: each of said drawers comprise a latch and an actuator; and saiddrawer manual override is configured to mechanically unlatch all of thedrawers when actuated with the hardware key.
 20. The medical station ofclaim 19, further comprising: a cassette manual override configured tomechanically unlatch the cassette system from the moveable cart uponactuation with a hardware key.